Matt Cahill has cultivated an image as a designer of cutting-edge dietary supplements. His current company, Driven Sports, markets a top-selling pre-workout powder called Craze. / Handout

by Alison Young, USA TODAY

by Alison Young, USA TODAY

A leading sports supplement retailer is the latest to suspend sales of the pre-workout powder Craze in the wake of a USA TODAY investigation of the product's maker.

Bodybuilding.com general counsel Bill Carter said Monday the online retailer pulled Craze out of its supplement store late Friday while it seeks further testing of the product. The popular website also has removed Craze from its list of nominees for 2013 Pre-Workout Supplement of the Year.

"The main message is there are too many questions, and my view on this is the responsible thing is to investigate it and hold off on sales until we get a definitive answer," Carter said.

The actions by Bodybuilding.com are the latest in the wake of a USA TODAY investigation of the product's maker, Matt Cahill, which revealed he has a history of putting risky products on the market. Cahill and his attorney, Aaron Goldsmith, did not immediately respond to an e-mail Monday. Cahill has repeatedly declined interview requests. His company, Driven Sports, has posted a statement on its website saying it is "disappointed" in USA TODAY's reporting and that Craze is a safe and legal supplement.

Walmart.com suspended sales of Craze on July 25 and last week Sen. Dick Durbin, D-Ill., repeatedly cited USA TODAY's investigation in announcing his reintroduction of a bill to strengthen oversight of supplements, including requiring products be registered with the U.S. Food and Drug Administration.

GNC and other online retailers, including Amazon.com, continue to sell Craze. "With third-party products, GNC is simply the retailer and, like all retailers, relies upon the representations and contractual warranties made by the vendor that the products are safe and compliant with all applicable laws and regulations," GNC said in a recent statement to USA TODAY. Amazon did not respond to repeated requests for comment.

Carter said it may take several weeks before Bodybuilding.com can have an independent lab conduct additional tests on Craze, as well as further evaluate the methodology used by a lab hired by Cahill and another lab hired by an industry competitor that have reached differing conclusions about whether Craze contains amphetamine-like substances.

"We're not discontinuing the product," Carter said, adding that Bodybuilding.com is not returning any of the product it still has in its warehouses while it awaits test results. "We're just simply, as a precaution, making sure these tests are done properly."

However Craze is now out of the running for the website's supplement awards, Carter said. "In response to the initial article in USA TODAY, our folks withdrew Craze from contention for the supplement awards this year," he said. By the time the retailer completes its testing, it will be too late for Craze to be put back into contention, he said. Last year Craze won the website's title of 2012 New Supplement of the Year, based on votes by website users, and was in the running in the pre-workout category this year.